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                                                                   Exhibit 10.79

                                SECOND AMENDMENT

         SECOND AMENDMENT dated as of August 13, 1998, (the "Amendment"), with
respect to the Credit Agreement dated as of August 20, 1997 (such agreement as
it has been amended prior to the date hereof, the "Credit Agreement"), by and
among PDK LABS INC. and FUTUREBIOTICS, INC., as Co-Borrowers (the
"Co-Borrowers"), and EUROPEAN AMERICAN BANK, a New York banking corporation
("EAB"), as Agent and as a Bank and the Banks party hereto.

                                    RECITALS

         The Co-Borrowers have requested and the Banks have agreed, subject to
the terms and conditions of this Amendment, to waive and amend certain
provisions of the Credit Agreement as herein set forth. Capitalized terms used
herein and not defined herein shall have the meanings given to them in the
Credit Agreement.

         Accordingly, in consideration of the premises and of the mutual
covenants and agreements hereinafter set forth, the parties hereto agree as
follows:

         I.       Amendments.

         Section 1.1. Section 1.1 of the Credit Agreement is hereby amended by
inserting the following definitions therein immediately prior to the definition
of "Debt":

                  "Consulting Agreement" means a consulting agreement to be
executed by and between PDK and Michael Krasnoff having a term of not less than
three (3) years pursuant to which Mr. Krasnoff shall provide consulting services
to PDK in the areas of marketing, finance, administration and mergers and
acquisitions at least sixteen (16) Business Days per month and which shall
include a non-compete agreement which will prohibit Mr. Krasnoff from being
employed by or from providing consulting services to any competitor of PDK,
which agreement shall be reasonably satisfactory to the Banks.

         Section 1.2. The definition of the term "Revolving Credit Commitment"
contained in Section 1.1 of the Credit Agreement is hereby amended by deleting
the chart therefrom and by substituting the following in its place:


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         Bank                                        Commitment
         ----                                        ----------

         EAB                                         $5,300,000

         National Bank of Canada                     $2,350,000

         Bank Leumi USA                              $2,350,000

         Section 1.3. The definition of the term "Revolving Credit Note"
contained in Section 1.1 of the Credit Agreement is hereby amended by inserting
the following phrase at the end thereof: ", or any note issued in substitution
or replacement thereof."

         Section 1.4. The definition of the term "Term Note" contained in
Section 1.1 of the Credit Agreement is hereby amended by inserting the following
phrase at the end thereof: ", or any note issued in substitution or replacement
thereof."

         Section 1.5. Article 6 of the Credit Agreement is hereby amended by
inserting the following in a new Section 6.20 at the end thereof:

                Section 6.20. Year 2000. Any reprogramming or other corrective
                modifications required to permit the proper functioning, in and
                following the year 2000, of (i) Co-Borrower's and their
                Subsidiaries' computer systems and (ii) equipment containing
                embedded microchips (including systems and equipment supplied by
                others or with which the Co-Borrowers' or their Subsidiaries'
                systems interface) and the testing of all such systems and
                equipment, as so reprogrammed, will be completed by January 1,
                1999. The cost to the Co-Borrowers and their Subsidiaries of
                such reprogramming, modifications and testing and of the
                reasonably foreseeable consequences of year 2000 to the
                undersigned and its subsidiaries (including, without limitation,
                reprogramming errors and the failure of others' systems or
                equipment) will not result in the occurrence of an Event of
                Default or result in a Material Adverse Change. Except for such
                of the reprogramming and modifications referred to in the
                preceding sentence as may be necessary, the computer and
                management information systems of the Co-Borrowers and their
                Subsidiaries are, and with ordinary course upgrading and
                maintenance, will continue for the term of this Agreement to be,
                sufficient to permit the Co-Borrowers to conduct their business.

         Section 1.6. Section 8.11 of the Credit Agreement is hereby amended and
restated to provide in its entirety as follows:


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                "Fail to maintain Michael B. Krasnoff (i) in a reasonably active
                full time capacity as the President of PDK and as an officer to
                Futurebiotics, responsible for the day to day operations of each
                of the Co-Borrowers or (ii) as a consultant to PDK and
                Futurebiotics pursuant to the terms of the Consulting
                Agreement."

         II. Conditions. The amendments provided for pursuant to Section I
hereof shall become effective only upon satisfaction of the following conditions
precedent:

             (a) The Agent shall have received each of the following, in form
and substance satisfactory to the Agent and its counsel.

                 (i)      This Amendment and amended and restated Revolving
                          Credit Notes executed by the Co-Borrowers in favor of
                          each Bank;

                 (ii)     a certificate of the Secretary of Compare Generiks,
                          Inc. (the "New Guarantor") dated the date of this
                          Amendment, attesting to all corporate action taken by
                          such entity, including resolutions of its Board of
                          Directors authorizing the execution, delivery and
                          performance of its Guarantee and each other document
                          to be delivered pursuant to this Agreement, together
                          with certified copies of the certificate or articles
                          of incorporation and the by-laws of the New Guarantor;
                          and, such certificate shall state that the resolutions
                          and corporate documents thereby certified have not
                          been amended, modified, revoked or rescinded as of the
                          date of such certificate;

                 (iii)    a certificate of the Secretary of the New Guarantor,
                          dated the Closing Date, certifying the names and true
                          signatures of the officers of such entity authorized
                          to sign the Facility Documents and the other documents
                          to be delivered by such entity under this Agreement;

                 (iv)     a certificate of a duly authorized officer of each of
                          the Co-Borrowers, dated the date of this Agreement,
                          stating that the representations and warranties in
                          Article 6 are true and correct on such date as though
                          made on and as of such date and that no event has
                          occurred and is continuing which constitutes a Default
                          or Event of Default;

                 (v)      a Guarantor Security Agreement duly executed by the
                          New Guarantor, together with (A) fully completed and
                          executed financing statements on Form UCC-1, in proper
                          form for filing duly filed under the Uniform
                          Commercial Code in all jurisdictions necessary or, in
                          the reasonable discretion of the Agent, desirable to

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                          perfect the security interests to be granted hereunder
                          and under the Guarantor Security Agreement and (B) UCC
                          search results identifying all of the financing
                          statements on file with respect to the New Guarantor
                          in all jurisdictions referred to under clause (A)
                          hereof, indicating that no party claims an interest in
                          any of the Collateral;

                 (vi)     a favorable opinion of counsel for the New Guarantor
                          dated the Closing Date, in form and substance
                          satisfactory to the Agent and its counsel;

                 (vii)    satisfactory evidence that the New Guarantor is duly
                          organized, validly existing and in good standing under
                          the laws of their respective jurisdictions of
                          incorporation and each other jurisdiction where
                          qualification is necessary; and

                 (viii)   such other documents, instruments, agreements,
                          approvals, opinions and evidence as the Agent may
                          reasonably require.

         III.    Miscellaneous.

                 (a) This Amendment shall be governed by and construed in
accordance with the laws of the State of New York.

                 (b) All terms used herein shall have the same meaning as in the
Credit Agreement, as amended hereby, unless specifically defined herein.

                 (c) This Amendment shall constitute a Facility Document.

                 (d) As expressly amended hereby, the Credit Agreement remains
in full force and effect in accordance with the terms thereof. The Credit
Agreement is ratified and confirmed in all respects by the Co-Borrowers. The
amendments herein are limited specifically to the matters set forth above and
for the specific instance and purposes for which given and do not constitute
directly or by implication an amendment or waiver of any other provisions of the
Credit Agreement or a waiver of any Event of Default or event which upon notice,
lapse of time or both would constitute an Event of Default which may occur or
may have occurred under the Credit Agreement or any other Facility Document.

                 (e) The Co-Borrowers hereby represent and warrant that (i) the
representations and warranties by the Co-Borrowers and each Guarantor pursuant
to the Credit Agreement and each other Facility Document are true and correct on
the date hereof, and (ii) after giving effect to this Amendment, no Event of
Default or event which upon notice, lapse of


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time or both would constitute an Event of Default exists under the Credit
Agreement or any other Facility Document.

                 (f) This Amendment may be executed in one or more counterparts,
each of which shall constitute an original, but all of which, when taken
together, shall constitute but one Amendment.

         IN WITNESS WHEREOF, the Co-Borrowers, the Agent and the Banks have
caused this Amendment and Waiver to be duly executed by their duly authorized
officers as of the day and year first above written.

                                            PDK LABS INC.


                                            By: ________________________  
                                            Title:


                                            FUTUREBIOTICS, INC.


                                            By: ________________________      
                                            Title:


                                            EUROPEAN AMERICAN BANK,
                                            as Agent and as a Bank


                                            By: ________________________  
                                            Title:


                                            BANK LEUMI USA, as a Bank


                                            By: ________________________  
                                            Title:


                                            NATIONAL BANK OF CANADA, as a Bank


                                            By: ________________________ 
                                            Title: